One of the words commonly thrown around by social justice advocates is "privilege". A privilege is simply some sort of benefit or advantage that a certain group has. It's a fairly basic concept, but I'm not sure I'm a fan. It seems to breed a lot of misconceptions, like the idea that privileges are always bad.
As an example, one privilege straight people have is the ability to go through life without labels for their sexual identity. Arguably, this privilege is unavoidable, as long as straight people are in the majority. All the same, if you are aware of this privilege, you should understand why it is insensitive to tell queer people not to bother with labels.
Another big misconception is the idea that groups are ordered from most privileged to least privileged. In truth, two groups can each be privileged over the other in different ways. For example, consider white women and black men. It may be the case that one group has more privileges than the other (supposing that you found some way to quantify "more privileges"), but nonetheless, each group has at least a few privileges that the other does not.
As another example, consider aromantic and romantic asexuals.* Romantics are privileged over aromantics because people are less likely to think they are devoid of all emotion. Aromantics are privileged over romantics because in non-romantic relationships they generally aren't expected to be sexual.
*If you don't recall, romantic asexuals are the ones who are interested in romantic relationships, and aromantics are the ones who are not.
I feel this is a fairly obvious point, and if people miss it, it's because they just haven't taken a moment to think about it. I guess this will be a short post!
For the fallacy geeks: What kind of logical fallacy is this? I'm thinking it's a false dilemma: either group A has privileges over group B, or group B has privileges over group A. Or maybe it's tu quoque: "I have privileges? You have privileges too!" This is a fallacy because pointing out another person's privileges does nothing to refute the existence of one's own privileges.